U.S. patent number 10,150,369 [Application Number 15/398,771] was granted by the patent office on 2018-12-11 for bi-directional overrunning clutch.
This patent grant is currently assigned to Super ATV, LLC. The grantee listed for this patent is Super ATV, LLC. Invention is credited to Dennis Kent, Chris Shelton, Damon Stephan, Jordan E. Stephan, Ken Thornton.
United States Patent |
10,150,369 |
Thornton , et al. |
December 11, 2018 |
Bi-directional overrunning clutch
Abstract
Certain embodiments of the present disclosure describe a
differential assembly for allowing a vehicle to switch between
two-wheel drive and four-wheel drive. The differential assembly
includes a bearing assembly positioned between a race gear and
output hubs. An armature plate is rotationally coupled to the
bearing assembly and a clutch plate is positioned to engage the
armature plate. A biasing member biases the clutch plate to engage
the armature plate and allow the bearing assembly to transmit
torque between the race gear and output hubs. When electricity is
provided to an electromagnet, the electromagnet exerts a magnetic
force on the clutch plate that is sufficient to overcome the bias
of the biasing member so the clutch plate does not engage the
armature plate and the bearing assembly does not transmit torque
from the race gear to the output hubs.
Inventors: |
Thornton; Ken (Canaan, IN),
Kent; Dennis (Madison, IN), Shelton; Chris (Madison,
IN), Stephan; Jordan E. (Hanover, IN), Stephan; Damon
(Madison, IN) |
Applicant: |
Name |
City |
State |
Country |
Type |
Super ATV, LLC |
Madison |
IN |
US |
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Assignee: |
Super ATV, LLC (Madison,
IN)
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Family
ID: |
59359460 |
Appl.
No.: |
15/398,771 |
Filed: |
January 5, 2017 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170210226 A1 |
Jul 27, 2017 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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62281216 |
Jan 21, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16D
41/067 (20130101); B60K 17/02 (20130101); B60K
23/08 (20130101); B60K 17/346 (20130101); F16D
27/112 (20130101); F16H 48/06 (20130101); B60Y
2400/82 (20130101); B60K 2023/0858 (20130101); B60Y
2400/80 (20130101) |
Current International
Class: |
B60K
23/08 (20060101); F16D 41/067 (20060101); B60K
17/02 (20060101); F16D 27/112 (20060101); B60K
17/346 (20060101); F16H 48/06 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1702947 |
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Nov 2005 |
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CN |
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201107845 |
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Aug 2008 |
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CN |
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63069060 |
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Mar 1988 |
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JP |
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WO 2015058765 |
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Apr 2015 |
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WO |
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Other References
Machine Translation of Abstract for JP 63069060A by Lexis Nexis
Total Patent on Jul. 21, 2015, (3 pages). cited by applicant .
Machine Translation of CN1702947A by Lexis Nexis Total Patent on
Jul. 21, 2015, ((5 pages). cited by applicant .
Machine Translation of CN201107845Y by Lexis Nexis Total Patent on
Jul. 21, 2015, (7 pages). cited by applicant .
Machine Translation of WO2015058765A1 by Lexis Nexis Total Patent
on Jul. 21, 2015, (8 pages). cited by applicant.
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Primary Examiner: Beauchaine; Mark J
Attorney, Agent or Firm: Woodard, Emhardt, Moriarty, McNett
& Henry LLP
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent
Application No. 62/281,216, filed Jan. 21, 2016; which is
incorporated herein by reference.
Claims
The invention claimed is:
1. A differential assembly comprising: a ring gear defining a
hollow interior opening; an engageable output hub positioned in
said hollow interior of said ring gear, wherein said output hub
includes two ends and each end of said output hub is adapted to be
coupled with a driven shaft; a bearing assembly including a
plurality of bearings, wherein said bearing assembly is positioned
between said ring gear and said output hub, and wherein said
bearing assembly has a first position in which said bearings engage
both said ring gear and said output hub assembly so that torque is
transferred from said ring gear to said output hub assembly, and
wherein said bearing assembly has a second position in which said
bearings do not engage said ring gear and said output hub assembly
so that the ring gear does not transfer torque to said output
assembly; an armature plate rotationally coupled to said bearing
assembly; a clutch plate that is selectively engageable with said
armature plate to selectively resist rotation of said armature
plate; an electromagnet; an electrical coupler adapted to
electrically connect said electromagnet to an external power
supply; a biasing member, wherein said biasing member biases said
clutch plate to engage said armature plate, putting said bearing
assembly into said first position; and, wherein when electricity
from the external power supply is provided to said electromagnet,
said electromagnet exerts magnetic force on said clutch plate that
is sufficient to overcome the bias of said biasing member so that
said clutch plate does not engage said armature plate.
2. The differential assembly of claim 1, wherein when electricity
from said external power supply is provided to said electromagnet
and said electromagnet exerts magnetic force on said clutch plate,
said bearing assembly is in said second position.
3. The differential assembly of claim 1, wherein said bearings are
in said second position when said clutch plate is not engaged with
said armature plate.
4. The differential assembly of claim 1, wherein said clutch plate
is configured to cause drag on said armature plate when said clutch
plate engages said armature plate.
5. The differential assembly of claim 1, wherein when electricity
is provided to said electromagnet, said electromagnet does not
apply sufficient force to said armature plate to put said bearing
assembly in said first position.
6. The differential assembly of claim 5, wherein said armature
plate comprises a nonferrous material.
7. The differential assembly of claim 1, wherein said biasing
member comprises a spring.
8. The differential assembly of claim 1, wherein said bearing
assembly includes a roll cage, wherein said roll cage defines
roller openings, and wherein a roller bearing is held in each of
said roller openings.
9. The differential assembly of claim 1, further comprising a main
housing cap, wherein said main housing cap defines at least one
opening for receiving said at least one biasing member.
10. The differential assembly of claim 9, wherein said main housing
cap defines a slot for receiving said electromagnet.
11. The differential assembly of claim 1, wherein said armature
plate includes a finger and wherein said finger is adapted to
rotationally couple said armature plate with said bearing
assembly.
12. The differential assembly of claim 1, wherein said clutch plate
is located between said electromagnet and said armature plate.
13. The differential assembly of claim 1, wherein said clutch plate
is located between said biasing member and said armature plate.
14. A vehicle comprising: the differential assembly of claim 1; two
front wheels and two rear wheels; a power source operationally
connected to a first drive shaft operationally connected to said
two front wheels through the differential assembly of claim to
selectively drive said two front wheels, and wherein said power
source is operationally connected to a second drive shaft adapted
to drive said two rear wheels.
15. A differential kit assembly comprising: a main gear housing; a
pinion gear wherein said pinion gear is operationally attached to a
drive shaft and wherein one end of said pinion gear is inserted
into said main gear housing; a ring gear including an inner
diameter with a variable geometry and defining a hollow interior
opening, wherein said ring gear is operationally connected to said
end of said pinion gear which is inserted into said main gear
housing; an output hub assembly inserted into said hollow interior
of said ring gear, wherein said output hub assembly defines a
splined opening for receiving a driven shaft; a bearing assembly
including a plurality of bearings, wherein said bearing assembly is
positioned between said ring gear and said output hub, and wherein
said bearing assembly has a first position in which said bearings
engage both said ring gear and said output hub assembly so that
torque is transferred from said ring gear to said output hub
assembly, and wherein said bearing assembly has a second position
in which said bearings do not engage said ring gear and said output
hub assembly so that the ring gear does not transfer torque to said
output assembly; a main housing cap defining a first and second
slot and a first opening within a hollow interior; a clutch plate
inserted into said first slot within said main housing cap; an
electromagnet inserted into a second slot within said main housing
cap; an electrical coupler adapted to electrically connect said
electromagnet to a power supply; a biasing member inserted into a
first opening in said main housing cap, wherein said biasing member
biases said clutch plate to engage said armature plate; wherein
when electricity from the external power supply is provided to said
electromagnet, said electromagnet exerts magnetic force on said
clutch plate sufficient to overcome the bias of said biasing member
so that said clutch plate does not engage said armature plate.
16. The differential assembly of claim 15, wherein said bearings
are in said first position when said clutch plate engages said
armature plate.
17. The differential assembly of claim 15, wherein said bearings
are in said second position when said clutch plate is not engaged
with said armature plate.
18. The differential assembly of claim 15, wherein said clutch
plate is configured to cause drag on said armature plate when said
clutch plate engages said armature plate.
19. The differential assembly of claim 15, wherein when electricity
is provided to said electromagnet, said electromagnet does not
apply sufficient force to said armature plate to put said bearing
assembly in said first position.
20. The differential assembly of claim 19, wherein said armature
plate comprises a nonferrous material.
Description
BACKGROUND
This disclosure is in the field of vehicle differentials.
Four-wheel drive is a useful feature for vehicles that are used in
situations where traction may be an issue. For example, off-road
vehicles may have four-wheel drive for navigating dirt roads,
gravel roads, or bumpy terrain. Four-wheel drive may also be useful
in rainy and snowy conditions to provide increased traction and
improved acceleration. However, in some cases when traction is not
an issue, four-wheel drive may not be necessary. Two-wheel drive
can improve fuel economy and produces less wear and tear on the
engine and the drive train of the vehicle. Therefore, it may be
beneficial for the vehicle to be able to switch between operating
in two-wheel drive and four-wheel drive when necessary.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a vehicle including a
differential assembly.
FIG. 2 is a perspective view of differential assembly.
FIG. 3 is an exploded perspective view of the differential assembly
of FIG. 2.
FIG. 4 is an exploded perspective view of a ring gear assembly from
the differential assembly of FIG. 2.
FIG. 5 is a perspective view of a ring gear from the ring gear
assembly of FIG. 4.
FIG. 6 is a perspective view of a bearing assembly from the ring
gear assembly of FIG. 4.
FIG. 7 is an exploded view of a cap housing assembly from the
differential assembly of FIG. 2.
FIG. 8 is a front cross-sectional view of the cap housing assembly
of FIG. 7 with internal components removed.
FIG. 9 is a front cross-sectional view of the cap housing assembly
of FIG. 7 connected to the ring gear assembly of FIG. 5.
FIG. 10A is a cross-sectional representation of a bearing assembly
between a ring gear and an output hub in a four-wheel drive
available position when power is not supplied to an
electromagnet.
FIG. 10B is a cross-sectional representation of a bearing assembly
between a ring gear and an output hub in an engaged position to
allow transfer of torque between the ring gear and the output
hub.
FIG. 10C is a cross-sectional representation of a bearing assembly
between a ring gear and an output hub in an unengaged, two-wheel
drive position when power is supplied to an electromagnet.
DETAILED DESCRIPTION OF THE DRAWINGS
Reference will now be made to certain embodiments and specific
language will be used to describe the same. It will nevertheless be
understood that no limitation of the scope of this disclosure and
the claims is thereby intended, such alterations, further
modifications and further applications of the principles described
herein being contemplated as would normally occur to one skilled in
the art to which this disclosure relates. In several figures, where
there are the same or similar elements, those elements are
designated with the same or similar reference numerals.
The present disclosure pertains to a differential that is
selectively engageable between two-wheel drive and four-wheel
drive. Aspects of the present disclosure include a differential
assembly including a main housing assembly, a ring gear assembly,
and a cap housing assembly. The main housing assembly may include a
housing that defines a hollow interior. A pinion gear may be
attached to the housing so that a portion of the pinion gear
extends into the hollow interior of the housing and another portion
of the pinion gear extends outside the housing. The portion of the
pinion that extends outside the housing may operationally connect
with a drive shaft of a vehicle.
The ring gear assembly may include a ring gear that defines a
hollow interior opening. An interior surface of the ring gear may
include ridges so that the interior surface has a variable
geometry. A bearing assembly may be inserted into the hollow
interior opening of the ring gear. The bearing assembly may include
bearings that are held by spring clips and biased to be positioned
between the ridges on the interior surface of the ring gear. The
bearing assembly may be rotationally coupled to an armature plate.
A pair of output hubs may be inserted into an opening defined by
the bearing assembly, constraining the bearings of the bearing
assembly between the interior surface of the ring gear and the
output hubs. Each of the output hubs may define an axle opening for
receiving the axle of a wheel from a vehicle.
The cap housing assembly may include a cap housing that defines a
hollow interior with various openings for insertion of additional
components. For example, cap housing may define a magnet slot for
an electromagnet and may define biasing member openings for holding
biasing members. Cap housing assembly may also include a clutch
plate that is positioned to interact with the electromagnet and the
biasing members.
The cap housing assembly is attached to the main housing assembly
and the ring gear assembly is positioned between the two
assemblies, in the hollow interiors of the cap housing assembly and
the main housing assembly. The ring gear assembly is positioned so
that the ring gear is operationally attached to the portion of the
pinion gear that is located in the interior of the main housing
assembly. The ring gear assembly is also positioned so that the
clutch plate from the cap housing assembly may engage the armature
plate.
In certain embodiments, the clutch plate is located between the
biasing members and the armature plate and is also located between
the electromagnet and the armature plate. When no electricity is
provided to the electromagnet, the biasing members bias the clutch
plate so that it engages and causes drag on the armature plate.
Because the armature plate is rotationally coupled to the bearing
assembly, drag is also produced on the bearing assembly. When the
rotation of the bearing assembly slows, the bearings are moved to a
location near the ridges of the interior surface of the ring gear.
While in this position, if the front wheels of the vehicle slip,
the ring gear starts to rotate faster than the output hubs, and the
bearings become wedged between the ridges on the ring gear and the
output hubs. When the bearings are wedged in this position, torque
is transferred from the ring gear to the output hubs, and the
vehicle is in four-wheel drive.
When electricity is provided to the electromagnet, the
electromagnet exerts a magnetic force on the clutch plate that is
sufficient to overcome the bias of the biasing members so that the
clutch plate does not engage the armature plate. This allows the
armature plate, and the bearing assembly, to freely rotate. When
there is no drag on the armature plate, the bearings in the bearing
assembly are maintained in a relatively centered position between
the ring gear and the output hubs. The bearings are not wedged
between the ring gear and the output hubs, so there is no torque
transfer between the ring gear and the output hubs. In this
arrangement, the vehicle is in two-wheel drive.
The term "engage" as used in this description means that two or
more mechanisms or components are connected so that a motion or
action of one of the mechanisms or components has an effect on the
motion or action of another mechanism or component. This effect can
be the result of direct contact between the two mechanisms or
through an operational connection in which intermediary components
connect the engaged mechanisms even though there is no direct
contact.
The term "rotationally coupled" as used in this description means a
link between two components wherein rotation of one of the
components causes rotation of the other component. The components
may be in direct contact or the coupling may include intermediary
pieces.
FIG. 1 is a schematic view of a vehicle 10. Vehicle 10 includes a
power source 12. Power source 12 could be an engine, a transmission
connected to the engine, or any other source of power. Vehicle 10
also includes a front differential assembly 14, a center
differential assembly 16, and a rear differential assembly 18.
Front differential 14 is connected to power source 12 by a drive
shaft 22. Power source 12 is connected to center differential 16 by
a drive shaft 24. Center differential 16 is connected to rear
differential 18 by a drive shaft 26. In some embodiments, the
center differential 16 could be incorporated into the transmission
(not shown) of the vehicle. In other embodiments, the rear
differential 18 may also be incorporated into the transmission.
Front wheel axles 31, 32 connect front wheels 30 to front
differential 14 and drive front wheels 30. Rear wheel axles 33, 34
connect rear wheels 35 to rear differential 18 and drive rear
wheels 35.
FIGS. 2-3 show an embodiment of front differential assembly 14.
Differential assembly 14 includes a main housing assembly 40, a
ring gear assembly 50, and a cap housing assembly 75. Rear
differential 18 may be set up similarly to front differential
14.
Main housing 40 includes a housing 41 that defines a hollow
interior 42 and a pinion gear 44. One end of pinion gear 44 extends
into interior 42 of housing 41, and the other end of pinion gear 44
extends outside of housing 41. The portion of pinion gear 44 that
extends outside of housing 41 may be connected to drive shaft
26.
An exploded view of ring gear assembly 50 is shown in FIG. 4. Ring
gear assembly includes a ring gear 52 that defines a hollow
interior opening 53. As seen in FIG. 5, the outer portion of ring
gear 52 may be splined so that ring gear 52 may be connected to the
end of pinion gear 44 that extends into interior 42 of housing 41.
This connection allows pinion gear 44 to drive ring gear 52. An
interior surface 55 of ring gear 52 that surrounds interior opening
53 includes ridges 54, producing a variable geometry within opening
53.
A bearing assembly 65 defining an opening 68 may be fit into hollow
interior opening 53 of ring gear 52. As shown in FIG. 6, bearing
assembly 65 includes bearings 66 that are positioned in openings
defined by the body of bearing assembly 65. Spring clips 67 bias
bearings 66 so that they float in the center of the openings in the
body of bearing assembly 65.
A torsion spring 56 may be attached to a side of ring gear 52 and
held in place by a torsion spring retainer 60. An armature plate 62
may be positioned on torsion spring retainer 60 on the opposing
side of ring gear 52. Armature plate 62 may be positioned so that
fingers 63 extending from armature plate 62 contact bearing
assembly 65 when bearing assembly 65 is inserted into interior
hollow opening 53.
Output hubs 70, 72 may be mated to each other and inserted into
opening 68 of bearing assembly 65 (see FIG. 3). The insertion of
output hubs into opening 68 of bearing assembly 65 places bearings
66 between interior surface 55 of ring gear 52 and output hubs 70,
72. Output hub 70 defines an axle opening 71 for receiving rear
axle 33. Output hub 72 defines an axle opening 73 for receiving
rear axle 34.
An exploded view of cap housing assembly 75 is shown in FIG. 7. Cap
housing assembly 75 includes a cap housing 76 that defines an
interior portion 77. As shown more clearly in FIG. 8, interior
portion 77 includes a magnet slot 78 and a biasing member opening
79. An armature opening 80 is positioned adjacent to magnet slot 78
and biasing member opening 79. A spacer opening 81 is positioned at
the edge of interior portion 77 adjacent to armature opening
80.
An electromagnet 87 may be fit into interior portion 77 within
magnet slot 78. An electrical coupler 86 is electrically connected
to electromagnet 87 and extends exteriorly from cap housing 76. In
the embodiment shown, electromagnet 87 is a ring magnet; however,
in other embodiments, different shapes other than an annular ring
may be used for electromagnet 87. Additionally, in some
embodiments, multiple magnets may be used and inserted into
separate magnet slots 78 in interior portion 77. Multiple openings
may be defined in cap housing 76 so more than one magnet may be
inserted into cap housing 76.
Biasing member 90 may be inserted into biasing member openings 79
in cap housing 76. In the embodiment shown, there are eight biasing
members 90 fit into respective openings 79 in cap housing 76.
However, in other embodiments, there may be more biasing members 90
or fewer biasing members 90. Also, the biasing members shown in
FIG. 7 are springs, but in other embodiments, any suitable
mechanism that can impart bias may be used.
In the embodiment shown in FIG. 8, slot 78 for electromagnet 87 is
positioned radially outward of opening 79 for receiving biasing
member 90. In other embodiments, the position of slot 78 and
opening 79 may be adjusted so that opening 79 for biasing member 90
is located radially outward of slot 78 for electromagnet 87.
Cap housing assembly 75 also includes a clutch plate 92, a spacer
94, and an O-ring seal 96. Clutch plate 86 is inserted into
armature opening 80 of interior portion 77 of cap housing 76 so
that it may interact with biasing members 84. Spacer 94 is
positioned into spacer opening 81. O-ring seal 90 fits around
housing 76 to provide a seal between cap housing assembly 75 and
main housing assembly 40.
FIG. 9 illustrates a cross-section of an assembled cap housing
assembly 75. Electromagnet 87 is fit within magnet slot 78, and
biasing members 90 are inserted into openings 79. Clutch plate 86
is inserted into armature opening 80 so that clutch plate 86 is
adjacent biasing members 90 and is adjacent to electromagnet 87. In
some embodiments, although not required, clutch plate 86 may be in
direct contact with biasing member 90. Armature plate 62 and
torsion spring retainer 60 are also inserted into armature opening
80 so that armature plate 62 is adjacent to clutch plate 92. Clutch
plate 92 is positioned between armature plate 62 and electromagnet
87 and also positioned between armature plate 62 and biasing member
90. Spacer plate 94 is inserted into spacer opening 81. An opening
defined through spacer plate 94 has a diameter that is large enough
to allow armature plate 62 and torsion spring retainer 60 to extend
through the opening.
In use, engagement of the bearings 66 in bearing assembly 65 with
the inner surface of ring gear 52 and output hubs 70, 72 allows
torque to be transferred from drive shaft 26 to rear wheel axles
33, 34. The rotational position of bearing assembly 65 with respect
to the ring gear 52 and the output hubs 70, 72 may be adjusted to
either allow engagement between bearings 66 and ring gear 52 and
output hubs 70, 72 or to disallow engagement when it is not desired
to transfer torque to rear wheel axles 33, 34.
To allow availability of four-wheel drive, differential assembly 14
is placed in a first state in which no power is provided to
electromagnet 87. In the first state, biasing members 90 bias
clutch plate 92 so that clutch plate 92 engages armature plate 62.
The interaction between armature plate 62 and clutch plate 92
causes drag on armature plate 62, causing armature plate 62 to
rotate more slowly than ring gear 52. Because armature plate 62 is
rotationally coupled to bearing assembly 65, for example by fingers
63, when armature plate 62 is caused to drag by clutch plate 92,
the rotation of bearing assembly 65 is also slowed with respect to
ring gear 52.
Slowing the rotation of bearing assembly 65 causes bearings 66 to
be positioned near ridges 54 on interior surface 55 of ring gear 52
(see FIG. 10A). In this position, bearings 66 contact ring gear 52,
but do not contact output hub 70 (or output hub 72), causing
bearing assembly 65 to rotate with ring gear 52 but not with output
hub 70. Therefore, torque is not transferred between ring gear 52
and output hub 70, and the vehicle remains in two-wheel drive.
However, when the front wheels 30 of vehicle 10 start to slip, the
rotational speed of drive shaft 26 starts to increase. Because ring
gear 52 is rotationally connected to drive shaft 26, the rotational
speed of ring gear 52 also increases. This causes the relative
rotational speed of ring gear 52 to increase with respect to output
hub 70. As the speed of ring gear 52 increases with respect to
output hub 70, bearing 66 slides backward with respect to ring gear
52 so that it is wedged between ridge 54 of ring gear 52 and output
hub 70 (see FIG. 10B). When bearing 66 is wedged between ring gear
52 and output hub 70, torque is transferred between ring gear 52
and output hub 70, putting vehicle 10 into four-wheel drive.
Once the front wheels 30 of vehicle 10 stop slipping, the
rotational speed of ring gear 52 decreases with respect to the
rotational speed of output hub 70 and bearings 66 are returned to
the position shown in FIG. 10A. Thus, the vehicle is returned to
two-wheel drive until the front wheels began to slip again.
An overrunning feature of differential 14 allows bearings 66 to
disengage from ring gear 52 even when the vehicle is in four-wheel
drive. As an example, when the vehicle is turning, it is desirable
for the outer wheel to rotate faster than the inner wheel because
the outer wheel has to cover more distance than the inner wheel.
The bearings 66 from the outer wheel are allowed to disengage from
ring gear 52 to allow the outer wheel to rotate faster than the
inner wheel and the drive shaft. If the inner wheel starts to slip
while the outer wheel is overrunning, the rotation speed of the
drive shaft will increase until it catches up with the speed of the
outer wheel, so that the outer wheel stops overrunning and is
driven by the drive shaft until traction is regained.
To keep the vehicle in two-wheel drive, even when the front wheels
of the vehicle are slipping, differential assembly 14 may be placed
in a second state in which an external power supply provides
electricity to electromagnet 87. This causes electromagnet 87 to
exert a magnetic force on clutch plate 92 that is sufficient to
overcome the biasing force of biasing members 90. This magnetic
force causes clutch plate 92 to stop engaging armature plate 62 and
stop applying drag force on armature plate 62. Therefore, armature
plate 62 is free to rotate with bearing assembly 65 with respect to
ring gear 52.
When no drag is exerted on armature plate 62, there is also no drag
exerted on bearing assembly 65. When there is no drag on bearing
assembly 65, bearings 66 are positioned between ring gear 52 and
output hub 70 so no torque is transferred between ring gear 52 and
output hub 70 (see FIG. 10C). Springs 67 support bearings 66 so
that they stay unengaged from ring gear 52 and output hub 70.
Because no torque is transferred between ring gear 52 and output
hub 70 axles 33, 34 are not driven by drive shaft 26.
In some embodiments, the external power supply may be controlled by
an electronic control system. In other embodiments, a driver of a
vehicle may selectively control the external power supply to
provide power to the electromagnet when desired.
Because the default position of the differential kit is to have no
power to the electromagnet and to have the clutch plate engage the
armature plate due to the bias of the biasing members, in the event
of a power failure, the vehicle will continue to have four-wheel
drive capability. If power to the electromagnet was required for
the vehicle to have four-wheel drive capability, a power failure
would prevent the vehicle from using four-wheel drive and
potentially cause safety issues if the driven wheels of the vehicle
lose traction and experience slippage.
While the disclosure has been illustrated and described in detail
in the drawings and foregoing description, the same is to be
considered as illustrative and not restrictive in character, it
being understood that only the preferred embodiments have been
shown and described and that all changes and modifications that
come within the spirit of the disclosure are desired to be
protected.
* * * * *